X-y switch for a telephone system



Aug. 19, 1952 H. SENGEBUSCH 2,607,355

X-Y SWITCH FOR A TELEPHONE SYSTEM Original Filed Dec. 18, 1947 4 Sheets-Sheet l INVENTOR. Hans Sengebusch A ffys.

H. SENGEBUSCH X-Y SWITCH FOR A TELEPHONE SYSTEM Aug. 19, 1952 4 SheetsSheet 2 Original Filed Dec.

INVENTOR Hans Sengebusch Aug. 19, 1952 Original Filed Dec. 18. 1947 H. SENGEBUSCH X-Y SWITCH FOR A TELEPHONE SYSTEM FIG. 2

FIG. 5

4 Sheets-Sheet 3 INVENTOR. Hans Sengebusch Affys Aug. 19, 1952 H. SENGEBUSCH X-Y swnca FOR A TELEPHONE SYSTEM 4 Sheets-Sheet 4 Original Filed Dec.

INVENTGR Hans Senggbusch BY W I voY ov wow 2:. a N om mm mm F m9 8 N 8v 8 o: @2 w 39 k Q0 8 x. 8 5 5 3% mv mm Q m 5 d3 5 mm 2 Q 8 m N N? 3 motions or flat type.

Patented Aug. 19, 1952 UNITED STATES PATENT OFF ICE X-Y SWITCH FOR A TELEPHONE SYSTEM Hans Sengebusch, Villa Park, Ill., assignor to Automatic Electric Laboratories, Inc., Chicago, 111., a corporation of Delaware Original application December 18, 1947, Serial No. 792,510. Divided and this application May 13,

1950,'Serial No. 161,780

2 Claims.

The present invention relates to-switcliing apparatus for telephone systems, and more particularly to such apparatus of the so-called'XY This application is a division of the copending application of Hans Sengebusch, Serial No. 792,510, filed December 18, 1947, now Patent No. 2,578,095, granted December 11, 1951.

' It is an object of the present invention to provide in switching apparatus of thetype including a primary carriage and a secondary carriage, improved mechanism for selectively operating the primary and secondary carriages and for restoring the secondary and primary carriages.

Another object of the invention is to provide in switching apparatus of the type noted, im-

proved mechanism of the direct drive type for selectively operating the primary and secondary carriages and improved spring mechanism for restoring the secondary and primary carriages.

A further object of the invention-is to provide in automatic switching apparatus including a drive bar,'improved motor means for selectively operating and for restoring the drive bar.

Further features of the invention pertain to the particular arrangement of the elements of the switching apparatus whereby the above-outlined and. additional operating features thereof are attained.

The invention, both as to its organization and vmethod of operation, together with further objects and advantages thereof, will best be understood by reference to the following specification taken in connection with the accompanying drawings, in which Figures 1 andlA, taken together, are a plan view, partly broken away,-of switching apparatus embodying thepresent invention; Figs. 2,and 2A, taken together, area front elevational view, ,partly broken away, of the switching apparatus; Fig- 3 is a bottom view of a fragmentary central portion of the base' plate of the switching apparatus. illustrating 403 and 404.

trated comprises the switching mechanism [00A of the direct drive type, contact bank structure .65 and supporting structure including two vertically extending and longitudinally spaced apart elements 40! and 402 and two horizontally extending and longitudinally spaced apart elements The switching mechanism 100A comprises a longitudinally extending base plate 32 provided with an upwardly turned front flange 132a and a rearwardly extending apron 32b. The

base plate 32 is supported upon the horizontal elements 403 and 404 and the rear edge thereof abuts the front edges of the vertical elements T401 and 402, the apron 32?) being arranged between'the longitudinally spaced apart vertical elements 4M and 402; whereby the normal position of the base plate 32 is accurately located by the vertical elements 40! and 402 upon the horizontal elements 403 and 404 so that the switching mechanism IO0A occupies a predetermined and exact position with respect to the'associated contact bank 65. The base plate 32 is normally retained in its normal position by locking'devices' disposed'at the opposite ends thereof and, cooperating with the horizontal elements 403 and404; the locking element 405 carried by the right-hand end of the base plate 32 being illustrated. Specifically, the locking element 405 is ,pivotally mounted by a screw 406 upon the front Iflange 32a and cooperates with a locking dog 401 secured by a screw 408 to the horizontal element '404.

Thus it will be understood that the base plate 32 may be readily removed with respect tothe supporting structure, including the vertical'elements 40! and 402 and the horizontal elements 403 and'404, merely by sliding it toward the front away from the contact bank 65 after the lockingelements 405, etc., have been disengaged. Accordingly, the switching apparatus 'l '00A may be readily placed upon and removed from the associated supporting structure for purposes of inspection and repair.

The contact bank'65 is of the ZOO-point of line ,type, each line including a positive conductor,

a positive conductor, a negativ conductor and two control conductors; whereby the contact bank 65'comprises 800 individual contact strips accessible to the switching apparatus IO0A. Specificallythe, contact bank 65 comprisesforty individual contact units 12 arranged in 'four groups of. teneach; each individual contact unit -12 comprising'twenty individual contact strips. Each individual contact unit l2 is of the bare contact striptype extending vertically in the contact bank 65. 'The contact bank 65 is acces- 3 sible to a number of switching mechanisms including the switching mechanism lililA, carried by the supporting structure in a vertical tier; whereby the contact bank 65 serves as a multiple between the difierent switching mechanisms for marking purposes.

All of the elements of the switching mechanism IGGA are secured to the base plate 32 so that they are properly positioned with respect to the contact bank when the base plate 32 is positioned upon the supporting structure as previously explained. Specifically, the switching mechanism EMA comprises contact controlling mechanism in the form of eight main individual wipers l, 2 and 3, t and 5, 6 and l, 8; the individual wipers i, 3, 5 and l constituting a'fir t wiper set having access to 100 lines, and the individual wipers 2, '5, 6 and 8 constituting a second wiper set having access to 100 lines. Specifically, the wipers i and 2 may comprise positive line wipers having access to the positive line conductors of the two groups of 100 lines each; the wipers 3 and 4 may comprise negative line wipers having access to the negative line conductors of the two groups of 100 lines each; the wipers 5 and 6 my comprise first control wipers having access to the first control conductors of the two groups of 100 lines each; and the wipers l and 8 may comprise second control wipers having access to the second control conductors of the two groups of 100 lines a each.

The two wiper sets are capable both of selective primary or longitudinal movement from the left toward the right and of selective secondary or lateral movement from the front toward the rear.

Specifically, the two wiper sets are capable of ten individual steps of longitudinal movement and of ten individual steps of lateral movement. Since each of the four sections of the contact bank are respectively associated with two corresponding ones of the individual wipers, each of the 200 lines is accessible to the two wiper sets. Moreover, when a given number of steps of longitudinal movement is imparted to the two wiper sets, the four corresponding contact units l2 are selected thereby; and when a given number of steps of lateral movement is imparted to the two wiper sets, eight individual contact strips comprising two lines in the four selected contact units 72 are selected. Accordingly, each combined longitudinal and lateral position of the two wiper sets corresponds to two individual lines in the contact bank 65 respectively selected by the two wiper sets. Finally, the first wiper set comprising the individual wipers l, 3, 5 and 1 is connected by a first set of flexible conductors, not shown, to a first terminal block, not shown, carried by the base plate 32; and the second wiper set comprising the individual wipers 2, i, B and 8 is connected by a second set of flexible conductors, not shown, to a second terminal block, not shown, carried by the base plate 32.

Considering new the construction of the switching mechanism NBA in greater detail, the base plate 32 carries a longitudinally extending guide rod 31, the oppositeend of which are anchored in openings formed in two blocks 33 directly secured to the upper surface of the base plate 32. A longitudinally slidable primary carriage IE is supported upon the guide rod 3! and comprises two centrally disposed rearwardly extending arms l9 and 29 and two outer rearwardly extending arms 34 and 35, as well as a centrally disposed forwardly projecting arm Mia The arms 34 and 35 carry downwardly projecting blocks 33 provided with openings through which the guide rod 3! extends; while the arm i602 carries a downwardly projecting fixture 5613 having a longitudinally extending slot, not shown, formed in the rear edge thereof into which the upper flange 160 of a guide element [6d rides, the guide element it'd being secured by two screws lee upon the front flange 32a of the base plate 32. Finally, the outer ends of the arms l9 and 2E] carry a longitudinally extending bracket 23!) disposed adjacent to the rear edge of the apron 3213; the bracket 28!! being secured to the outer ends of the arms I9 and 23 by two screws 203a. The primary carriage is has a normal longitudinal position toward the left and is capable of longitudinally sliding movement toward the right; the primary carriage It being guided in its primary movement by the cooperation between the fixture i612 carried by the arm 56a and the flange ltc of the guide element ltd carried by the front flange 32a of the base plate 32 and by the cooperation between the blocks 36 carried by the arms 34 and 35 and the guide rod 3 I.

A laterally slidable secondary carriage 9 is carried by the primary carriage it; the secondary carriage 9 being substantially T-shaped having a forwardly projecting stem 90. overlying the arm 25a of the primary carriage l6 and a longitudinally extending head So overlying the arms 34 and 35 of the primary carriage it. The outer end of the stem 9a carries a downwardly extending rivet 22 provided with a groove positioned in a laterally extending slot 21 formed in the arm We. Also the left-hand side of the arm ifia carries an upstanding pin 22a carrying a roller 22b engaging the left-hand edge of the stem 3a. Finally, two rollers I? are mounted on the lower surface of the head 9b and respectively engage the outer edge of the arm [9 and the outer edge of the arm 2%. The secondary carriage 9 has a normal lateral position toward the front and is capable of lateral sliding movement with respect to the primary carriage 16; the lateral sliding movement being guided by the cooperation between the rivet 22 and the slot 2i by the cooperation between the roller 22b and the adjacent edge of the stem 9a and by the cooperation between the rollers H and the adjacent outer edges of the arms l9 and The head 9b of the secondary carriage 9 carries four longitudinally spaced apart brackets l9, ll, 12 and I3 respectively secured thereto by screws lila, Ha, Mia. and The bracket in carries two rivets l4 supporting the main wipers l and 2 in longitudinally spaced apart relation with respect to each other by virtue of an arrangement including a plurality of intervening insulating strips; the bracket ll carries two rivets l4 supporting the main wipers 3 and 4 in longitudinally spaced apart relation with respect to each other by virtue of an arrangement including a plurality of intervening insulating strips; the bracket i2 carries two rivets I l supporting the main wipers 5 and 6 in longitudinally spaced apart relation with respect to each other by virtue of an arrangement including a plurality of intervening insulating strips; and the bracket l3 carries two rivets l4 supporting the main wipers l and 8 in longitudinally spaced apart relation with respect to each other by virtue of an arrangement including a plurality oi intervening insulating strips. The bracket20ll carries four longitudinally spaced apart upstanding insulating bushings 23], 232, 203 and 204 disposed between the respective pairs of main wipers; I.,2, and13, 4:and.5 6. and, 1, 8m OIdGI'i'tQF maintain theindividualwipers of each pair out-.1

of contact with each: other when they occupy,

theirfully-retractedpositions toward the front.

of 'the baseplate 32.

Theaprimary carriage. l6 comprises anormal longitudinal. position and. may be moved: step, by stepvtherefrom in the longitudinal direction.

from the left toward the right. as previously,

notedyan-d: the secondary carriage 9 comprises. a normal lateral position and may be moved:

step-by steptherefrom in the lateral direction from-ithe front toward the rear. as previously noted. In order to accomplish these movements of the primary carriage I3 .and'or the secondary carriage 9, an arrangement is provided comprising alongitudinallyextending drive'bar 30in the form-ofa rack having a normal longitudinal po! sition toward theleft and capable of steppedmovement in the longitudinal direction toward The longitudinal movement offthe rack 30-is guided by a stationary'fixture 95 se'-- cured to the right-hand end of the base plate 32. and'havinga slot formed therein receiving and the right.

guiding the right-hand enact the rack 30 and by a roller 30a mounted upon a pin 30b'carried by the primary carriage I6. The rack 30 is normally restrained in its normal longitudinal position toward theleft by a coil spring 89, one endofthe coil spring 89-being secured to a pin 9i carried by'the base plate 32 and the other end" of the coil spring 89 being secured to a pin 90 carried by the rack 30;

The primary carriage I6- has an opening 28 formed therein through which a vertically disposed pin 26- extends, the upper end of the pin being arranged in an opening formed in abracket 21 secured to the primary carriage I6 and the lower end being secured to a lower fix ture, not shown, carried by the primary car-- downwardly projecting pivot pin 39 supporting the left-hand end of a latch lever 31 as well as a leafspring 38 urging the latch lever 31 in the counterclockwise direction about the pivot pin 39'. The right-hand end of the latch lever 31 carries a rearwardly projecting latch 40 normally engaging a notch 42 formed in the front edge ofthe rack and a forwardly. projecting latch 41 adapted to engage any one often notches 43 provided in an upstandin latch plate 44 secured. to the front flange 32a adjacent to the right-handend thereof. The notches 43 formed in the latch plate 44 are spaced apart distances corresponding to the longitudinal steps or the primary carriage I6. Accordingly, it will be understood that the leaf spring v3i; normally urges the latch 40 into the notch 42 formed in the rack 30 thereby latching the primary carriage I6 to the rack 30. In order to control the position of the latch lever 31, an arrangement is provided comprising a shift magnet 96A provided with magnetic structure secured to the right-hand end'of the base plate 32. The shiftmagnet 96A carries a pivotpin 98 upon which an armature 91 ismounted, the outer end of the armature 9! carrying a pini 0.0. to which:therrear.= endtof :a-sllde? 99 is secured. Thebody portionofthe. slide"; is bent downwardly and arranged in aaguidinz; opening 99a formedin thebase plate and the front end of the slide 99: carries .a pin. I0.I.;to.:whi'ch-. the left-hand end of a lever I02. is secured,gthe;. right-hand end of the. lever I02; beingsecured to a screw. I03 carried by the base plate- 32".. Finally, the front end of the slide 99 carries;..a longitudinally extending upstanding trip 46.: dis-- posed between the front of the rack 30.; and a downwardly projecting lug 31w formedpn. the; extreme right-hand end-of the latching leverv 31'. Accordingly, the leafspring: 38' not only biases.- the latching lever 31:" in the; counterclockwise direction about the pivot pin 39, but it also causes; the lug 31a carried-thereby to-engage thestrip48: and urge it toward the rear; whereby the slide 99 is moved towardthe-rear rotating; thelover I02 in the-clockwise direction about the screw I03 and rotating the armature--91 in the clockwise directionabout the pivot pin-98.

In order to control movement of the rack 30 from-itsnormal longitudinal position toward the. right; an-arrangement is provided comprising; a; drive magnet 15A- provided withmagneticstruce ture including a heel piece 11 secured to the righthand end of the base plate- 32. The-heel-piece 'II carries a pivot pin I9 upon whichan airman.-

. ture' I8 is pivotally-mounted. Also; the right hand-end'of the base-plate 32- carries-an-upstanding pin a upon which an upper ratchetBB an'd a lower gear 85 are journaled, the ratchet 88; being rigidlysecuredtothegear=85. The teeth provided on the gear85' engage corresponding teeth 30a formed onthe'front edge of the-rack- 30; and" the ratchet cooperates with a pawl 81 carried by the armature 18. More particularly. the pawl 81 is-pivotally mounted=on a pivot-pin 81a disposedon the outer end ef'the armature" and is normally biased in the clockwise-direction. about the pivot pin 81ainto engagement with the ratchet by an arrangement comprising a, coil spring 88 extending between thearmature. I8 andthe outer left-hand end of thepawl" 8.1. The-armature 18-is normally biased'in the clock'pwise direction about the-pivot pin 19 by an. arrangement including a coilspring 84; one end of the coil spring 84 beingsecured to an upstanding pin 84a carried by thebase plate-32= and theother end of the coil spring 84- beingsecured to the extreme-outer end of the armature I8. the extreme outer end-oi thearmaturelflcarriesa detent 86 adapted to cooperate with the-teethon the gear 85 in a manner more fully explained hereinafter; Further a detent 92* is pivotallymounted upon the fixture by a pivot pin 93 and is normally biased in the-clockwise direc tion into engagement with the ratchet 88- by an arrangement including-a coilspring 94 extending between the detent'92 and-the fixture.

Further the switchingmechanism I00A com.- prises a release magnet I05'A providedwithmag; netic structure secured to the right-hand end of the base plate 32; The'release magnet I05A is provided with an armature I06. mounted upon a pivot pin lfllcarried by the base plate 32and cooperating with a release dog I09 mounted upon a pivot'pin I IOcarried by the base plate'32'; The release dog 109 is normally biased in the-counterclockwise direction about the pivot pin H0 by an arrangementincluding a coil spring I09a extendingbetween the release dog I09 and the fixture' 95-. The left-hand end of the release dog I09 comprises two fingers III and- H2 respecward the front; and the rack 39 normally oc-,

cupies its normal longitudinal position toward the left. Moreover, the latch lever3l is normally biased by the leaf spring 38 in the counterclockwise direction about the pivot pin 39; whereby the latch 40 engages the notch 42 formed in the rack 39 locking the primary carriage IE to the rack 38. At this time, when the winding of the drive magnet 15A is energized, the armature T8 is attracted and rotated in the counterclockwise direction about the pivot pin 19 against the bias of-the coil spring 84; whereby the pawl 81 engaging the associated tooth on the ratchet 88 rotates the ratchet 88 and consequently the gear 85 one step in the clockwise direction about the pivot pin 85a. At the end of the stroke, the detent 86 formed on the outer end of the armature 18 engages the associated tooth on the gear 85 preventing further rotation thereof in the clockwise direction. Also, at this time, the detent 92 urged by the coil spring 94 rides over one tooth on the ratchet 88 and engages the next adjacent tooth thereon, thereby to prevent return movement of the ratchet 88 inthe counterclockwise direction. When the winding of the drive magnet TSA is then deenergized, the armature I8 is released and rotated in the clockwise direction about the pivot pin 19 by the coil spring 84, the detent 86 disengaging the associated tooth on the ratchet 88 in-order to condition the pawl 81 to drive the ratchet 88 an additional step in the clockwise direction. When the gear 85 is thus rotated one step in the clockwise direction, the teeth thereon engaging the teeth 30a on the rack 39 slide the rack 39 from its normal longitudinal position one step toward the right against the bias of the coil spring 89. When the rack 39 is thus driven from its normal longitudinal position one step toward the right, the primary carriage l6 latched thereto by the latch 48 moves therewith from its normal longitudinal position one step toward the right. When the primary car-' riag'e H is driven away from its normal longitudinal position one step toward the right, the two wiper sets are brought into longitudinal alignment with respect to the two corresponding first groups of ten lines in the two lOO-line groups in the associated contact bank 85. 'Thus itwill be understood that by energizing the winding of the drive magnet 15A a number of times, while the primary carriage IE is latched to the rack 30 by the latch 40, the primary carriage I6 is driven a corresponding number of steps away from its normal longitudinal position toward the right in order to cause the two wiper sets to select the two corresponding groups of ten lines in the two loo-line groups in the associated contact bank 65.

, After the primary carriage I6 has been operated as described above the required number of steps away from its normal longitudinal position, the winding of the shift magnet 93A is energized;

whereby the armature 91 is attracted and rotated v in the counterclockwise direction about the pivot pin 98 moving the slide 99 toward the front of the base plate 32 through the pin I89. When the slide 99 is thus moved toward the front of the plate 44.

base plate 32 the lever I02 is rotated about the screw I03 due to the connection of the slide 99 thereto by the pin IUI; whereby the trip 46 is moved toward the front flange 32a rotatingthe latch lever 31 in the clockwise direction aboutthe pivot pin against the bias of the leaf'spring 38 due to the engagement between the trip 46 and the lug 31a carried by the latch lever 31. More particularly, when the primary carriage I6 is moved away from its normal longitudinal-position one or more steps in the longitudinal direction toward the right, the latch lever 31 is moved therewith and into alignment with a corresponding one of the notches 43 formed in the latch Accordingly, at this time when the latch lever 37 is rotated by the trip 46 in the clockwise direction about the pivot pin 39, the latch 49 disengages the notch 42 formed in the rack 39 and the latch 4| engages the aligned notch 43 formed in the latch plate 44; hence, the primary carriage I6 is unlatched from the rack 30 by the disengagement of the latch 49 and the notch 42; and the primary carriage I6 is latched against further movement in the longitudinal direction by the engagement between the latch 4| and the aligned notch 43.

At this time while the winding of the shift magnet 96A is energized, the winding of the drive magnet A is energized; whereby the armature 78 causes the pawl 81 to drive the ratchet 88 an additional step in the clockwise direction cans-- ing the gear 85 to drive the rack 30 an additional step in the longitudinal direction toward the right. At this time the smooth front surface of the rack 30 disposed between the teeth 39a formed on the right-hand end thereof and the teeth formed on the left-hand end thereof engaging the gear rides to the right past the latch 49; whereby the notch 42 formed in the rack is no longer aligned with respect to the latch 49. At this time the winding of the shift magnet 96A may be deenergized in order to release the armature 91; whereby the armature 91 is rotated only through a small angle in the clockwise direction about the pivot pin 98 since the slide 99 is not forced rearwardlyby the leaf spring 38 acting through the latching lever 31 and thetrip 48. Specifically, the end of the latch engages the associated smooth front edge of the rack 38 relieving the force of the latch lever '31 upon the trip 46. Accordingly the smooth front surface of the rack 38 restrains the latch lever 31 in its rotated position in the clockwise direction about the pivot pin 39; whereby the latch 4| is restrained in the aligned notch 43 formed in the latch plate 44. 7

Accordingly, at this time the primary carriage I6 is latched against further longitudinal movement and the rack 30 is free to slide with respect thereto; whereby the rack 98 is slid with respect to the primary carriage l9 effecting rotation of the gear 29 one step in the clockwise direction with the pivot pin 28. Thus the pin 29 is rotated one step in the clockwise direction causing the gear 25 to be rotated therewith in order to drive the meshing rack24'one step toward the rear of the base plate 32. Specifically, the secondary carriage 9 is moved away from its normal lateral position one step in the lateral direction toward the rear of the base plate 32 with respect to the primary carriage l8; whereby the two wiper sets supported by the secondary carriage 9 are driven into engagement with the first contact strips in the contact units 12 previously selected by the longitudinal movement of the primary carriage I6. Thus the two wiper sets mentioned select the first two corresponding lines in the previously selected two groups of ten lines each. Thus it will beunderstood that by energizing the winding of the drive magnet 15A an additional number of times following the energization of the winding of the shift magnet 96A and the consequent operation of the latch lever 31, the secondary carriage 9 may be driven a corresponding number of steps toward the rear of the base plate 32. Hence, it will be understood that by energizing the winding of the drive magnet 15A the additional number of times mentioned the secondary carriage 9 is driven a corresponding number of steps away from its normal lateral position toward the rear of the base plate 32 in order to cause the two wiper sets to select two corresponding lines in the two previously selected groups of ten lines each. Thereafter one of the two lines thus selected may be selected by external relays, not shown, merely by selecting one of thetwo wipersets mentioned.

Recapitulating, primary operation of the drive magnet 15A prior to operation of the shift magnet 96A effects primary operation of the primary carriage I6; while secondary operation of the drive magnet 15A subsequent to operation of the shift-magnet 96A effects secondary operation of the secondary carriage 9. For example, in the event the drive magnet 15A is operated X number of times prior to operation of the shift magnet 96A, and is then. operated Y number of times subsequent to operation of the shift magnet 96A, the primary carriage I6 is operated X steps in the longitudinal direction and the secondary carriage 9 is operated Y steps in the lateral direction; whereby the X longitudinal position and. the Y lateral position set the two wiper sets carried by the secondary wiper carriage 9 to select the two corresponding lines in the two groups of 100.1ines each.

In order to release the switching mechanism IOA, after operation thereof in the manner described above, the winding of the release mag net I A is energized attracting and rotating the armature I06 in the counterclockwise direction about the pivot pin I01, whereby the release dog I09'is rotated in the clockwise direction about the screw I I0; against the bias of the coil spring I09a. When the release dog I09 is thus operated, the

fingers I II and H2 respectively engage the de-- tent 92 and the pawl 81 rotating the detent 921 in the counterclockwise direction about the screw 93 against the bias of the coil spring 94 and rotating the pawl 81 in the counterclockwise direction about the pivot pin 81a against the. bias of the coil spring 88'. Accordingly, the detent 92' and, the pawl '81 are moved out of engagement with the two corresponding teeth on the ratchet; whereby the ratchet 88 and the gear 89 arefree to rotate upon the pin 85a. At this time-the coil spring 89 restores the rack toward the left causing the teeth on the left-hand end thereof to rotate the gear 29 in the counterclockwise direction; whereby the pin 26 carrying thegear, 25 is thus rotated bringing about retraction therein into alignment with the latch 40 carried by the latch lever 31; whereby the leaf spring 38 rotates the latch lever '31 in the counterclockwise direction about the pivot pin 39 forcing the latch 40 into the notch 42. Accordingly, at this time the latch 4I carried by the latch lever 31 disengages theassociated notch 43 formed in the latch plate 44; whereby the primary carriage I6 is latched to the rack 30 for movement therewith and is unlatched with respect to the base plate 32. Continued movement of the rack 30 toward the left bythe coil spring 89 effects sliding of the primary carriage I6 toward the left along the guide rod 3 I. Accordingly, the rack 30 is restored toward the left back into its normal longitudinal position carrying the primary carriage I6 therewith; whereby the primary carriage I6 is restored toward the left back into its normal longitudinal position.

After the secondary'carriage 9 and the primary carriage I6 have been released and restored back into the normal lateral position and the normal longitudinal positions thereof, respectively, the winding of the release magnet I0'5a is deenergized; whereby the armature I06 is released and rotated in the clockwise direction about the pivot pin I0'I' by the coil spring I09a incident to rotation of the release dog I09 in the counterclockwise direction, thereby about the pivot pin IIO. At

this time the fingers III and H2 carried by therelease dog I09 disengage the detent 92 and a pawl 81, respectively; whereby the coil spring 94 rotates the detent 92 in the clockwise direction about the pivot pin 93 back into engagement with an associatedtooth of the ratchet 88 and the coil spring 88 rotates the pawl 81 in the clockwise direction about the pivot pin 81a back into engagement with an associated tooth in the ratchet 88. At this time the switching mechanism I 00A .is; completely released.

Further: the switching mechanism IO0A comprises the primary control contact structure 205 shown in: Figs. 3 and 4 and including an insulatlngbase plate. 205a secured to the lower surface of the centraljportion of the apron. 32b of the base" place 32Iadjacent to the rear edge thereof by a pair of screws 206 extending through tapped openings formed in the apron 32?). Also the structure 205 comprises two insulating bushings 293a surrounding the screws 206 and a conducting guide rail 2I'I extending therebetween. The guide rail 2II is disposed below the insulating base plate 205a. and carries longitudinally slidable wiper structure 208 including two individual Wipers 209and 2I0 and a connecting insulator 2| 3. A band 2I2a, is secured to the insulator 2I 3 and surrounds the guide rail 2 and the wiper 2I0 is provided with two downwardly extending tabs 2 I2- embracing the sides of the guide rail 2'I I. Further, the insulating base 205a carries a seriesv of ten longitudinally spaced apart contacts 201 cooperating with the wiper 209; the individual contacts 201 being spaced apart longitudinally distances corresponding to the respective steps of the primary carriage I6 in the longitudinal direction. Finally, the insulator 2 I 3 comprises twotabs 2 I 3a arranged in spaced apart relation and'receiving a lug 2I4 secured to the lower surface of the bracket 200. The wiper structure 208 occupies a normal longitudinalposition when the primary carriage I6 occupies its normal longitudinal position; and when the primary carriage I6 is moved step by step away from its normal longitudinal position toward the right, the wiper structure 208 is likewise moved away from its normal longitudinal position step by step toward the right. As noted above, the longitudinal spacings of the individual contacts 28'! correspond to the steps of the primary carriage l; whereby the wiper 209 engages a given individual contact 257 when the primary carriage it occupies its corresponding longitudinal stepped position. Finally, the wiper 2ID engages the guide rail 2 at each step of the wiper structure 258. Thus it will be understood that the guide rail 2H may be selectively connected to the individual contacts 291 at the corresponding individual steps of the primary carriage which arrangement may be employed for control and supervisory purposes in an obvious manner.

Also the switching mechanism 100A comprises a set of primary off-normal switch springs 41. The set of switch springs 4! is mounted upon a bracket 49 by suitable intervening insulating strips; which bracket 49 is suitably secured to the left-hand upper surface of the base plate 32. Also the switching mechanism [00A comprises a set of secondary off-normal switch springs 52. The set of switch springs 52 is mounted upon a bracket 55 by suitable intervening insulating strips; which bracket is suitably secured to the left-hand upper surface of the base plate 32. The set of switch springs 4'! is provided with an operating rod 48 slidably mounted in two aligned openings formed in the brackets 49 and 50 and carries an insulator 580, on the left-hand end thereof for operating the individual switch springs of the set 47. The right-hand end of the operating rod 43 engages a fixture 5! carried on the arm 34 of the primary carriage I6. Accordingly, when the primary carriage I6 is moved away from its normal longitudinal position one step toward the right, the fixture 5| disengages the right-hand end of the operating rod 48 causing the insulator 48a carried on the left-hand end of the operating rod 48 to operate the individual contacts of the set 41. A fixture 54 is secured to the left-hand upper surface of the base plate 32 and carries a pivot pin 54a upon which a bellcrank 53 is mounted. The bell-crank 53 is substantially L-shaped including one leg extending longitudinally toward the right and carrying a roller 65 and another leg extending forwardly and carrying a pivot pin 53a to which a link is secured, the link 56 supporting an insulator 56a connected to the individual switch springs of the set '52. The roller normally engages a fixture 55 secured to the secondary carriage 9. When the secondary carriage 9 is moved away from its normal lateral position one step toward the rear, the fixture 55 disengages the roller 65; whereby the bell-crank 53 is rotated in the counterclockwise direction about the pivot pin 54a causing the link 55 to operate through the insulator 56a, the individual switch springs of the set 52. ly, the set of switch springs 41 is operated when the primary carriage I6 is operated from and back to its normal longitudinal position; and similarly, the set of switch springs 52 is operated when the secondary carriage 9 is operated from and back to its normal lateral position.

Further the switching apparatus IOUA comprises a set of impulsing springs 58 mounted upon a bracket 59 by suitable intervening insulating strips; which bracket 59 is suitably secured to the left-hand upper surface of the base plate 32. The switch springs 58 are operated by an insulator 50a carried by a lever 50 mounted upon a pivot pin 5i and carrying a roller 62 on the outer end thereof that cooperates with a comb-like fixture According- 63 suitably secured to the arm 34 of the primary carriage 16. As the primary carriage I5 is moved from its normal longitudinal position toward the right, the teeth on the comb-like fixture 63 carried thereby engage and disengage the roller 52; whereby the lever 6% is pivoted first in the clockwise direction about the pivot pin 5! and then in the counterclockwise direction about the pivot pin 6!; whereby the insulator We carried thereby operates the set of switch springs 53 to transmit a corresponding series of impulses.

Considering now the construction and arrangement of the contact bank 65 associated with the switching apparatus [A in greater detail, it will be observed, as shown in Figs. 1, 1A, 5 and 6, that each of the four sections of the contact bank 55 comprises an assembly of ten individual contact units 12 retained in assembled relation by a plurality of bolts 13. Specifically each contact unit 12 comprises a centrally disposed insulating body 6'! in the form of a fiat strip having ten laterally spaced apart grooves formed in each surface thereof and carrying ten individual fiat strip conductors 66 on each surface thereof arranged in the grooves mentioned. The strip conductor 66 disposed on each side of the insulating body 61 are retained in place in the grooves mentioned by a series of vertically spaced apart clamps 12A. Each of the clamps 12A comprises front and rear insulating sheets 68 and 69 overlying the respective surfaces of the strip conductors 66 arranged in the grooves mentioned formed in the respective front and rear surfaces of the insulating body 61, front and rear clamping plates 68a and 69a and two intervening spacing blocks 10. Finally, the elements of each clamp 12A are retained in assembled relation by two eyelets II respectively extending through the spacing blocks 10, as well as the adjacent ends of the clamping plates 65a and 69a and the adjacent ends of the insulating sheets 68 and 69. The eyelets 10 are of the hollow variety having an opening extending therethrough adapted to receive the clamping bolts 13 previously noted; whereby ten of the contact units 12 may be securely retained in stacked relation. The thickness of the insulating sheets 68 and 69 and the clamping plates 68a and 69a are such that the bodies 61 of each two adjacent contact units 12 are spaced longitudinally from each other a distance corresponding to one longitudinal step of the primary carriage l6 of the switching mechanism IDOA so that when the ten assembled contact units 12 comprising a section in the contact bank 65 are supported by the associated supporting structure adjacent to the switching mechanism IOOA that the contact strips 66 carried by the bodies 61 are spaced longitudinally corresponding to the various longitudinally stepped positions of the two associated main wipers carried by the secondary carriage 9. Also it is noted that the clamps 12a are spaced vertically apart in order to define a plurality of effective contact sections of each contact unit 12 therebetween that are, in turn, respectively accessible to the various wiper sets of the various switching mechanism A, etc., arranged in the vertical tier in the supporting structure. Accordingly, the sections of the contact strips covered by the clamps "52A constitute connecting multiples between the effective contact sections thereof that may be employed for marking purposes between the wiper sets of the various switching mechanisms having access thereto.

Recapitulating it is pointed out that the switching mechanisms I A, etc, are carried by the supporting structure including the elements 4M 402, 403,. 404,, etc., in vertically stacked relation in what maybe termed the Z direction. Likewise, the contact bank 65 extends-yertically providing adjacent sections spaced. apart substantially the fixed distance Z in the 2 direction and-accessible to the respective switching mechanisms. In each section of thecontact bank 65, the ten individual contact units: 12 are spaced longitudinally apart substantially the -fixed, distance X'* in the X directionand corresponding to the longitudinal steps of the primary carriages of the switching mechanisms IUOA, etc. Further, the four sections of the contact bank 65 are spaced longitudinally apart corresponding to the distances between the various pairs of wipers in the two individual sets of switching mechanisms in the two wiper sets of the switching mechanisms IOOA, etc. Finally, in each contact unit 12, the individual contact strips 66 are spaced apart laterally the substantially fixed distance Y in the Y direction corresponding to the lateral steps of the secondary carriages of the switching mechanisms IOOA, etc.

In view of the foregoing, it is apparent that there has been provided in automatic switching apparatus of the type including primary and secondary carriages, improved mechanism for selectively operating the primary and secondary carriages and for restoring the secondary and primary carriages.

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. Switching apparatus comprising a, support, a primary carriage carried by said support and having a normal primary position and mounted for primary movement with respect thereto, a secondary carriage carried by said primary carriage and having a normal secondary position and mounted for secondary movement with respect thereto, a contact controlling element carried by said secondary carriage, a drive bar carried by said support and having a normal position and mounted for movement with respect thereto, a spring normally biasing said drive bar into its normal position, means including a drive magnet for imparting to said drive bar selective movements in a given direction away from its normal position against the bias of said spring, latching means normally restraining said drive bar against return movement in the opposite direction back into its normal position, means including a release magnet for tripping said latching means so that said spring moves said drive bar in said opposite direction back into its normal position, drive mechanism having a normal position and an operated position, said drive mechanism in its normal position being responsive to initial movement in said given direction of said drive bar for correspondingly operating said primar carriage away from said normal primary position, said drive mechanism in its operated position being responsive to continued movement in said given direction of said drive bar for correspondingly operating said secondary carriage away from said normal secondary position, said drive mechanism in its operated position being responsive to initial movement :in said-opposite. direction of saidztdriveibar for correspondingly restoring said secondary carriageto said normal secondary position, said drive mechanism in its normal position being responsive to continued movement in said opposite directionof said drivebar' for correspondingly restoring said primary carriage. to said normal primary position, means including a shift magnet for moving said drive mechanism from its normal position to its operated position, restraining means operative in response to said continued movement in said given direction of said drive bar for holding said drive mechanism in its operated position independently of said shift magnet, and means responsive to restoration of said secondary carriage back into said normal secondary position for releasing said restraining means and for moving said drive mechanism from its operated position back to its normal position.

2. Switching apparatus comprising a support, a primary carriage carried by said support and having a normal primary position and mounted for primary movement with respect thereto, a secondary carriage carried by said primary carriage and having a normal secondary position and mounted for secondary movement with respect thereto, a contact controlling element carried by said secondary carriage, a drive bar carried by said support and having a normal position and mounted for movement with respect thereto, a spring normally biasing said drive bar into its normal position, means including a drive magnet and an associated pawl and ratchet mechanism for imparting to said drive bar selective step-by-step movements in a given direction away from its normal position against the bias of said spring, latching means normally restraining said drive bar against return movement in the opposite direction back into its normal position, means including a release magnet for tripping said latching means so that said spring moves said drive bar in said opposite direction back into its normal position, drive mechanism having a normal position and an operated position, said drive mechanism in its normal position being responsive to initial movement in said given direction of said drive bar for correspondingly operating said primary carriage away from said normal primary position, said drive mechanism in its operated position being responsive to continued movement in said given direction of said drive bar for correspondingly operating said secondary carriage away from said normal secondary position, said drive mechanism in its operated position being responsive to initial movement in said opposite direction of said drive bar for correspondingly restoring said secondary carriage to said normal secondary position, said drive mechanism in its normal position being responsive to continued movement in said opposite direction of said drive bar for correspondingly restoring said primary carriage to said normal primary position, means including a shift magnet for moving said drive mechanism from its normal position to its operated position, restraining means operative in response to said continued movement in said given direction of said drive bar for holding said drive mechanism in its operated position independently of said shift magnet, and means responsive to restoration of said secondary carriage back into said normal secondary position for releasing said restraining means and for moving said drive mecha- 15 16 nism from its operated position back to its nor- UNITED STATES PATENTS mal positlon' Number Name Date HANS t H 2,052,059 Sengebusch Aug. 25, 1936 2,148,824 Llenzen Feb. 28, 1939 5 2,218,833 Sengebusch Oct. 22, 1940 REFERENCES CITED 2,218,834 Sengebusch Oct. 22, 1940 The following references are of record in the 2,433,256 Baker Dec. 23, 1947 file Of this patent: FOREIGN PATENTS 10 Number Country Date- 85,768 Switzerland Mar. 10, 1936 176,065

Great Britain Mar. 6, 1920 

